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Opening a link to a calculator connected by USB

In order to open the link to the calculator, the steps are the following:

1. Create a context using cahute_create_context().

2. Open a link using cahute_open_simple_usb_link() with the device address.

3. Profit!

4. Call cahute_close_link() to close the link.

5. Call cahute_destroy_context() to destroy the context.

Note

If there are multiple calculators connected by USB to your system, you can manage multiple or a specific subset of them by:

• Detecting available USB devices using cahute_detect_usb(). See Listing calculators connected by USB for steps to do so;

• Opening a link to a specific USB device using cahute_open_usb_link().

An example program to do this is the following:

/* Compile using: gcc open-usb-link.c `pkg-config cahute --cflags --libs`. */

#include <stdio.h>
#include <cahute.h>

int main(void) {
    cahute_context *context;
    cahute_link *link = NULL;
    int err, ret = 1;

    err = cahute_create_context(&context);
    if (err) {
        fprintf(
            stderr,
            "cahute_create_context() has returned error %s.\n",
            cahute_get_error_name(err)
        );
        return 1;
    }

    err = cahute_open_simple_usb_link(context, &link, 0);
    if (err) {
        fprintf(
            stderr,
            "cahute_open_simple_usb_link() has returned error 0x%04X.\n",
            err
        );
        goto fail;
    }

    /* Profit! */
    printf("Link successfully opened!\n");

    ret = 0;
fail:
    if (link)
        cahute_close_link(link);

    cahute_destroy_context(context);
    return ret;
}